US 2004/0227814 A1, which is incorporated herein by reference, shows a double exposure method for a camera system of a vehicle that synthesizes first and second images obtained using different exposure times.
DE 102006028624 A1, which is incorporated herein by reference, shows an exposure-adaptive image sensor with a control device, said control device enabling the integration time to be reduced effectively.
The synthesis of two images that were recorded at different times results in the blurring of objects that change their positions quickly.
If illumination is insufficient, a reduced integration time may result in objects or markings that are poor in contrast and, as a result, cannot be reliably detected any more.